To decorate and protect the surfaces of products, resin films and glass and the like are attached to the surfaces.
However, the resin films and glass decorating and protecting the surfaces of products sometimes get cloudy and dirty to reduce visibility and good appearance of the products.
To prevent reduction of visibility and good appearance of products, a hydrophilization treatment is applied to the resin films and glass.
As a technique of the hydrophilization treatment, for example, preventing formation of fine water drops by applying an anticlouding agent containing a surfactant, etc., to the surface of an object, thereby improving wettability of the coating surface with water has been proposed (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2004-263008). However, the technique proposed herein has a problem. Although the surface can be easily converted to be hydrophilic, the hydrophilic effect does not last long because of spray coating.
As another technique, using photocatalytic activity of TiO2 by placing a TiO2 layer having a photocatalytic function on a surface of a glass substrate, is proposed (see, for example, JP-A No. 2002-201045). However, the technique proposed therein has a problem. Since a sufficient amount of ultraviolet rays is required to express a photocatalytic function, TiO2 is applicable to limited sites.
As a technique for improving hydrophilicity of a transparent substrate surface, uniformly forming a micro concavoconvex surface due to an inorganic powder added to the film, on a substrate, thereby making the film to be hydrophilic is proposed (see, for example, JP-A No. 11-217560). However, the technique proposed herein has a problem. In the technique, a dispersion solution containing a silicon dioxide fine powder is applied to soda glass, heated and cured at 120° C. for 30 minutes. Thus, a substrate material is limited.
Another technique is proposed in which convexoconcave portions are formed in a silicon plate or glass by photolithography and etching and oxidized to render the surface of convexoconcave portions to be hydrophilic, as a structure for maintaining hydrophilicity for a long term (see, for example, JP-A No. 2001-212966). However, the technique proposed herein has a problem in that this technique cannot be applied to a substrate made of a resin.
Another technique for maintaining hydrophilicity by forming a micro structure in a nano-meter size is proposed (see, for example, JP-A No. 2007-187868). However, in the technique proposed herein, disclosure of hydrophilicity is limited to the cases where a substrate is made of glass such as automobile front windows and side windows and no disclosure is made of the case where a substrate is made of a resin such as an acrylic resin.
In the circumstances, it is presently desired to provide a hydrophilic laminate capable of maintaining hydrophilicity for a long term without limitation of applicable sites even if an easily processed substrate made of a resin is used, and a method for manufacturing such a hydrophilic laminate, an antifouling laminate using the hydrophilic laminate, a product using the hydrophilic laminate, and a method for manufacturing the product, and an antifouling method using the hydrophilic laminate.